Dental mallet.



Patented May I3, |902.

J. W. THATCHER.

DENTAL MALLET.

(Application led. Jan. 25, 1902.

(No Modal.)

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JOSEPH W. THA'IOIIER, OF SAN FRANCISCO, CALIFORNIA.

ENTAL MALLET..

SPECIFICATION forming part of Letters Patent No. 700,160, dated 13,1902. Application led January 25,1902. Serial No. 91,162; (No model.)

To @ZZ whom t mf//g/ concern:

Be it known that I, JOSEPH W. Tnnronnn, a citizen of the United States,residing at San Francisco, in the county ot San Francisco and State ofCalifornia, haveinvented certain new and useful Improvements in DentalMallets; and I do hereby declare the following to be a full, clear, andexact description of the inven tion, such as will enable others skilledin the art to which it appertains to make and usc the same.

My present invention relates to improvements in dental mallets; and ithas for its objects to produce a mallet electrically operated and one inwhich the blow delivered follows each successive pressure of the instru.ment against the tooth-filling, thereby distinguishing the device fromthe mallets new on the market, in which as the electrical contact ismade a vibrating motion is assumed. The device is capable of producing abackward as well as a forward malleting blow, thereby rendering theinstrument especially valuable where certain diflicult cavities areencountered.

It is manifest that the device can be varied in size and utilized as ariveting, welding', cutting, or drilling` machine.

Other objects and advantages of the invention will appear in thefollowing specification, and the novel features thereof will beparticularly set forth in the appended claims.

I am enabled to accomplish the above results by the means illustrated inthe aecompanying drawings, in which- Figure 1 is an elevation of thecomplete device. Fig. 2 is a central vertical section of the same, thetooth being shown in dotted lines. Fig. 3 is an enlarged top View of theinsulating-disk and the partsv immediately connected thereto. Fig. f1 isa perspective View of the upper insulating-cap and removable yoke forconnecting` the electric wires with the instrument. Fig. 5 isa sectionon the line oo on of Fig. 1. Fig. G is a View of the insulating-disk,taken in the direction of the arrow in Fig. e. Fig. 'iis an enlargedsection of the lower portion of the device. Fig. 8 is an elevation ofthe same portion. Fig. 9 is a section on line y y of Fig. 7. Fig. 10 isa diagrammatical view of the solenoids, the contactplatesand thecross-reed, with the electrical connections therefor.

Referring now to the above views, 1 represents the tool-shank, to thelower portion of which is removably secured the tool 2, while the uppercontracted portion bears the pistons 3 and 4,'the latter beingintegrally formed on shank v1, while the former is screw-threadedthereon. Between these pistons 3 and t and yieldingly and normallyheldbetween them by means of the springs 5 and U is the sliding armature 7.

Secured to the upper extremity of the shank 1, but insulated therefromby means of the mica washers S, is the cross-reed 0.. Encircling thearmature 7 is the hollow iron core 10, about which are wound wires 11 toform the solenoids A and I5. This hollow core 10 is extended beyond thesolenoid B and is provided with a hollow interior flange 12 to limit thedownstroke of the piston 4. 'Io benefit the electrical action of thedevice, l have slotted longitudinally the core 10, as shown at 13 inFig. 5.

To the lower end of the core 10 I have connected the terminal casing 14Eby means of the threaded hollow plug 15. This plug 15 encircles theshank 1 and is provided with a longitudinal slot 16, into which thecross-pin 17 protrudes from the shank 1. Encircling the shank 1, butinterposed between the shank and the inner wall of the plug 15, are thethimbles 1S and 19, which are heldv firmly against the pin 17 by meansof the springs 2O and 21. It will be noted that the iianges 22 on thethimbles 1S and 19 are provided to hold the pin 17 normally midwaybetween opposite ends of the slot 16.

On the upper projecting extremity of the hollow core 10 isscrew-threaded theinsulating-disk 23, the outer edge of which isscrew-threaded to removably receive the insulating-cap 21. Secured tothe upper surface of the disk 23 are the metal plates a, l), c, and d.From diametrically opposite points relative to the disk 23 andprotruding from the plates c and l) are the pins 25 and 2G, on which areadapted to removably clamp the perforated extremities of the metal yoke27, formed of two separate arms, each connected with one of the wiresIV. The plate a is IOS) formed with the bentback contact-lip 28, whilethe plate d has the projecting lip 22, which latter is directly overthelip 30, formed on plate c. One end of the wire from each solenoid isconnected to the plate I), while the opposite ends of the wires from theupper and lower solenoids are connected to the plates c and d,respectively.

As pressure is brought on the tool 2 by contact with the filling of thetooth, the reed 9, which is held normally midway between the lips 29 and30, as shown in Figs. G and l0, is forced upward into contact with lips28 and 29, thereby permitting the electricity to pass from the positivewire through one of the arms of the yoke 27 tothe plate d and throughthe reed 9 to the plate (l, then through the lower solenoid B to theplate i), and then out through the other arm of the yoke 27 to thenegative wire, and consequently the lower solenoid will be energized andAdraw armature 7 downward until it strikes piston 4, thereby producingthe desired downward blow. Pressure in the opposite direction on thetool 2 will cause the reed 9 to come in contact with the lip 30 andplate d, thereby energizing the upper solenoid A and causing thearmature to strike the upper armature 3, and in so doing produces abackward malleting blow.

From the foregoing description it will be readily understood that inorder to fill the tooth the angular tip of the tool 2 is inserted intothe cavity, and a forward or backward pressure of the tool on the sidesof the cavity will produce the forward and backward malleting blows, asheretofore explained.

I have incased the solenoids by an iron cylindrical cover C, which isheld in place by the removable rubber ferrule F.

When it is desired to remove the tool-shank l and connected parts, thepin 17 is removed and the reed 9 turned into the position shown indotted lines in Fig. 3, when the entire shank is free to be withdrawn.

By reference to FiO'. -l it is manifest that should occasion require itthe cap 24, yoke 27, and connected wires lV can be quickly and readilyremoved from the remaining parts of the instrument or as quicklyconnected ready for operation.

There are various forms which this device may take on and still bewithin the spirit of my invention, and I do not desire to confine myselfto the exact construction and location of parts herein shown anddescribed.

I claiml. A device of the class described consisting of a pair ofsolenoids, a tool-holder having a portion thereof movable through saidsolenoids, an armature slidingly mounted on said holder and in saidsolenoids and electrical connections.

2. A device of the class described consisting of alined solenoids, atool-holder movable in said solenoids, an armature slidingly mounted onsaid holder and yieldingly held in said solenoids, and electricalconnections so that movement of the holder in opposite directions willalternately energize said solenoids.

3. A device of the class described consisting of a solenoid, atool-holder, electrical contact devices operated by movement of saidholder, and an armature slidable on said toolholder and adapted toeffect said holder for the purpose set forth.

4. A device of the class described consisting of solenoids, atool-holder protruding from said solenoids, a pin passing through saidholder, thimbles encircling said holder and on opposite sides oi saidpin, and springs adapted to bear on said thimbles and return said pin toa normal position, andan armature in said solenoids and electricallyconnected to effect said holder.

5. A device of the class described consisting of solenoids, atool-holder, a reed on said holder, contact devices in the path of saidreed, a spring-yoke adapted to removably engage said contact devices,and electric connections between the several parts.

G. A device of the character described, consisting of solenoids, atool-holder having a portion thereof movable through said solenoids,electrical contact devices to coact with said solenoids, a yieldingelement between said contact devices movable by the said toolholder toalternately energize the solenoids, and an armature slidable on thetool-holder, and electrical connections.

7. In a device of the character described, the combination with a pairof solenoids, a tool-holder movable through said solenoids, pistonsarranged apart upon the tool-holder, an armature slidable within thesaid solenoids and adapted to engage the said pistons, and electricalconnections.

S. A device of the class described, consisting of alined solenoids, atool-holder, an armature operated by said solenoids and having amovement independent of the said toolholder, electrical means 'forenergizing said solenoids and means whereby the movement of the saidholder will cause the said solenoids to be energized alternately.

In testimony whereof l affix my signature in presence of two witnesses.

JOSEPH VI. 'llllATtfllEl-l.. lVitnesses:

Geenen PA'r'risoN, Emz. Kinofilm.

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